When caring for disabled persons or patients in a hospital ward, there is often use for various kinds of adjustable supports for headrests, seat backs, mattresses and similar uses. Also, adjustable supports are often applied in connection with equipment, e.g. lamp stands, especially on tables, tool holders and brackets for various applications, where adjustability is required for proper function or for convenience.
U.S. Pat. No. 6,758,808 discloses an adjustable support or stabilisation device including an elongated structure consisting of segments engaging each other in succession. Each segment is provided with opposed pivot surfaces at respective ends thereof, facing away from each other for contacting and abutting on an adjacent segment. The two opposed pivot surfaces of each segment are provided with complementing convex and concave, respectively, curving shapes that are generally partially cylindric and provided with teeth-like projections. The support is held in fixed position by means of a tensioning wire extending through the segments in the elongated structure as the teeth-like projections on abutting segments engage each other. The support of this U.S. patent is designed as an arm or bracket for stabilising tissue to perform surgery while the heart of the patient continues to beat. The mutually engaging teeth-like projections of the segments of the support extend along the curvature of the complementing pivot surfaces so as to guide the segments in their pivoting movement. Since the teeth-like projections extend along the curvature of the pivot surfaces, there is only friction to hold the support in fixed shape and position. Consequently, it is limited how great a load the support can carry or resist in use.
Due to the special application, the segments in the support of U.S. Pat. No. 6,758,808 are largest and widest at the base, becoming successively smaller towards the distal end. In production, this requires special moulds or manufacturing for each segment, depending on the position of the individual segment in the succession. Also, the segments and support according to this prior art are only adjustable in one plane due to the design of the segments and their pivot surfaces.
A further example of an adjustable support structure is disclosed in EP 2039271. In this construction, alternating circle cylindrical elements and substantially rectangular elements are assembled, in order to provide flexibility as to the shape of the structure. When being assembled, tightening of through going wires, the alternating circle cylindrical elements and substantially rectangular elements are locked mutually, allowing the elements to be mutually fixed, such that the assembled plurality of circle cylindrical elements and substantially rectangular elements represents the shape of a curve or the like. The structure according to EP2039271 therefore relies on at least two different elements in order to assemble a support. When branches or the like needs to be added further special elements, not disclosed, shall be used.